Add support for 100M on RTL8221B ports

Add Steamemo IG204 V1 support

doc/devices/STEAMEMO_IG204_V1.md

@@ -0,0 +1,43 @@
+# Steamemo IG204-V1
+
+Following is documentation for unmanaged switch marked as `IG204-V1`.
+
+Using SPI clamp in-board is the only method for initial installation.
+
+### Label specifications
+
+- **Name**: 2.5G Ethernet Switch  
+- **Model**: IG204 V1
+- **Ports**:  
+  - 4 × RJ45: 10/100/1000/2500 Mbps  
+  - 2 × SFP: 1000 / 2500 / 10000 Mbps  
+
+### What works (expected from label + similar devices)
+
+- Four 2.5GBASE-T RJ45 ports at 10/100/1000/2500 Mbps  
+- Two SFP ports supporting 1G, 2.5G and 10G modules 
+- LEDs
+
+### PCB overview
+
+**Board markings**  
+- Top silkscreen: PB-2131
+
+
+Top side
+
+<img src="photos/STEAMEMO_IG204_V1/PCB-top.jpg" width="600" />
+
+### Connectors
+### T7, serial console
+
+| `T7` pin | Signal      |
+| -------- | ----------- |
+| 1        | TX (Output) |
+| 2        | GND         |
+| 3        | RX (Input)  |
+| 4        | 3V3         |
+
+### Power supply
+
+Input power is delivered via barell plug, `12V 1A` adapter was provided.

machine.c

@@ -676,6 +676,58 @@ __code const struct machine machine = {
 
 void machine_custom_init(void) { }
 
+#elif defined MACHINE_STEAMEMO_IG204_V1
+__code const struct machine machine = {
+	.machine_name = "Steamemo IG204 V1",
+	.isRTL8373 = 0,
+	.min_port = 3,
+	.max_port = 8,
+	.n_sfp = 2,
+	.log_to_phys_port = {0, 0, 0, 6, 1, 2, 3, 4, 5},
+	.phys_to_log_port = {4, 5, 6, 7, 8, 3, 0, 0, 0},
+	.is_sfp = {0, 0, 0, 2, 0, 0, 0, 0, 1},
+	// Left SFP port (5)
+	// LED pin 9
+	.sfp_port[0].pin_detect = GPIO30_ACL_BIT3_EN,
+	.sfp_port[0].pin_los = GPIO37,
+	.sfp_port[0].pin_tx_disable = GPIO_NA,
+	.sfp_port[0].sds = 1,
+	.sfp_port[0].i2c = { .sda = GPIO39_I2C_SDA4, .scl = GPIO40_I2C_SCL3_MDC1 },
+	// Right SFP port (6)
+	// LED pin 24
+	.sfp_port[1].pin_detect = GPIO50_I2C_SCL2_UART1_TX,
+	.sfp_port[1].pin_los = GPIO51_I2C_SDA2_UART1_RX,
+	.sfp_port[1].pin_tx_disable = GPIO_NA,
+	.sfp_port[1].sds = 0,
+	.sfp_port[1].i2c = { .sda = GPIO41_I2C_SDA3_MDIO1, .scl = GPIO40_I2C_SCL3_MDC1 },
+	.reset_pin = GPIO_NA,
+	.high_leds = { .mux =  LED_27 | LED_28_SYS | LED_29, .enable = LED_28_SYS | LED_29 },
+	.port_led_set = { 0, 0, 0, 1, 0, 0, 0, 0, 1},
+	.led_sets = {
+			{
+				// RJ45 Amber LED (left)
+				LEDS_2G5 | LEDS_LINK,
+				// RJ45 Green LED (Right)
+				LEDS_2G5 | LEDS_1G | LEDS_100M | LEDS_10M | LEDS_LINK | LEDS_ACT,
+				0,
+				0,
+			},
+			{
+				// SFP LED
+				LEDS_10G | LEDS_5G | LEDS_2G5 | LEDS_1G | LEDS_100M | LEDS_LINK | LEDS_ACT,
+				0, // unused
+				0, // unused
+				0
+			},
+		},
+	.led_mux_custom = 1,
+	.led_mux = {
+		0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x0f, 0x20, 0x0d, 0x0e, 0x10, 0x11, 0x12, 0x14, 0x15, 0x16, 0x18, 0x19, 0x1a, 0x1c, 0x1d, 0x1e, 0x0c, 0x21, 0x22, 0x23
+	},
+};
+
+void machine_custom_init(void) { }
+
 #elif defined MACHINE_HI_K0801WS
 __code const struct machine machine = {
     .machine_name = "Hi-Source HI-k0801WS",

machine.h

@@ -23,6 +23,7 @@
 // #define MACHINE_LIANGUO_ZX_SWTGW215AS
 // #define MACHINE_ZX310S_4T2XH
 // #define MACHINE_ZX310S_4T2XT
+// #define MACHINE_STEAMEMO_IG204_V1
 // #define MACHINE_DEFAULT_8C_1SFP
 // #define MACHINE_HI_K0801WS
 // #define MACHINE_FNS1200P

rtlplayground.c

@@ -1406,9 +1406,9 @@ void idle(void)
 			cpy_4(linkbits_last, sfr_data);
 			// Handle link change of the RTL8221 PHY, adjust SDS mode, RTL8261BE always uses SDS_QXGMII
 			if (!machine.n_10g && p5_last != p5) {
-				if (p5 == 0x5) // 2.5GBit Mode
+				if (p5 == 0x5)	// 2.5GBit Mode
 					sds_config(0, SDS_HISGMII);
-				else if (p5 == 0x2) // 1GBit
+				else		// 1GBit and 100Mbit
 					sds_config(0, SDS_SGMII);
 			}
 			if (machine.n_10g)